Research On Flameout-preventing Pump Control System Used In Hydrostatic Driving System Of Towing Engineering Vehicle

The prime movers of hydrostatic steering driveline system can not only drive travelling system but also some hydraulic transmission device. The actual road and the working condition are complicated and changeful, the load power of the wheel adding the drive power of the hydraulic mechanism tends to exceed the maximal output power of the engine. When the engine is at overload functions, the operator handles the valve footplate and the gearlever on the basis of his experience and intuition. This measures need high quality of operator and is prone to extinguish the engine, resulting in security issue and effecting the efficiency of the engineering vehicle. Hydrostatic steering system accessorial with control device with high efficiency, strong anti-pollution ability and adaptive speed would combine to a ideal transmission system in a wide speed control interval. It can make the rotate speed and output torque of the engine adapt to the transformation of external load leading to avoid engine flameout, simply operation and enhancement of mechanical security and working efficiency.Through experiment and academic analysis, research has been made on anti-flameout pump control system in hydrostatic driving system of towing engineering vehicle.We have analyzed the parameters relationship between engine and variable pump as well as mechanism of anti-flameout pump control device. Variable pump-quantificational motor hydrostatic driving system mathematic model has been established. Emulational analysis based on Matlab/Simulink demonstrates the anti-flameout character in hydrostatic drive system consisted of pump control device and hydraulic motor.The measures that bring dynamic pressure feedback device to variable displacement and install accumulator in main hypertension of driving system enhance the damping ratio and traveling stability of hydrostatic driving system.The result shows that theory analysis is coincident with experiment result.During hydrostatic transmission, variable pump is the core of the towing engineering vehicle.It is a key of engineering vehicle traction system that how to control variable pump in an effective and credible way in order to reach the request of adaptive speed control of constant power.In order to avoid flameout frequently during vehicle traveling, variable pump displacement adaptive control reacting to load with hydraulic speed-react control technology turns out to be helpful to avoid engine flameout based on the characteristic of fall of engine rotate speed accompanied with augment of external load.It has extensive engineering prospect.